The general syntax of the grep commands is: You can use fgrep to find all the lines of a file that contain a particular word. For example, to list all the lines of a file named myfile in the current directory that contain the word dog, enter at the Unix prompt:
Outer core. The outer core of the Earth is a liquid layer about 2,300 km (1,400 mi) thick and composed of iron and nickel that lies above Earth's solid inner core and below its mantle.Its outer boundary lies 2,890 km (1,800 mi) beneath Earth's surface.ecause of its high temperature, modeling work has shown that the outer core is a low viscosity fluid (about ten times the viscosity of liquid metals at the surface) that convects turbulently. Eddy currents in the nickel iron fluid of the outer core are believed to influence the Earth's magnetic field.
Most magma that reaches the surface in volcanic eruptions comes from a part of Earth's mantle called the asthenosphere. The asthenosphere is a layer of solid rock that is near its melting point. Turning this solid rock into liquid magma means changing its temperature, pressure, and water content. Try your hand at melting rock to create magma. The first thing to try changing is the temperature. Your rock is a toasty 1,500 degrees Celsius, but it's still solid. Click on the words lower or raise to change the temperature your rock is subjected to inside Earth.